This article focuses on online political communication about Europe produced by French and Dutch political parties and NGOs in the context of the 2005 referendum on the European constitution, and compares this Internet-based communication with news about Europe in French and Dutch newspapers in the context of the same event. The aim of this study is to disclose the (sometimes hidden) frames within these various types of political communication, and determine whether these frames, conceptualized as common understandings of what constitutes ‘Europe’, are cross-nationally shared among political actors from various EU member states. This would be an indicator of the existence of a European public sphere. In the inductive phase of the study, three frames have been reconstructed through an in-depth analysis of a small representative sample of texts collected during the 2005 referendum campaign. In each frame Europe is portrayed in a different manner: (1) in the “Donor” frame Europe is portrayed as a successful joint venture; (2) in the “David vs. Goliath” frame as a superstate; and (3) in the “Invention” frame as out of control. In the deductive phase of the study, the three reconstructed frames were subsequently examined for their presence in a larger set of texts: 268 texts found on websites produced by political parties and NGOs and within newspapers. The most commonly shared understanding appeared to be the “Donor” frame, which was employed by most political actors in the two countries. Observed variations could be linked to the opinion an actor appeared to hold on the European constitution, and to a lesser degree to the actor type. Cross-national similarities in the employment of other two frames could mainly be observed among political parties.